Dissection of germline mutations in a sensitive and specific manner presents a continuing challenge. In dominantly inherited diseases, mutations occur in only one allele and are often masked by the normal allele. For example, it is estimated that 20-40% of both APC and hMSH2 mutations are difficult or impossible to detect with standard techniques based on PCR analysis of genomic DNA or RNA transcripts6-10. Thus there is a need in the art for a technique which is relatively simple to perform and which will detect a broad spectrum of mutations in genes of clinical interest.
It is an object of the invention to provide a method for detecting mutations in the germline.
It is another object of the invention to provide a method for detecting mutations which are not detected by standard methods.
It is yet another object of the invention to provide a method for detecting mutations which lead to diminished or loss of expression of a gene product.
These and other objects of the invention are provided by one or more of the embodiments described below. In one embodiment a method of detecting mutations in a gene of interest on a chromosome of a human is provided. The method comprises the steps of:
obtaining cells of the human;
fusing said cells to rodent cell recipients to form a human-rodent cell hybrid;
testing said human-rodent cell hybrid to confirm the presence of said chromosome of the human in said hybrid;
testing said hybrid which contains said chromosome to detect a protein product of said gene, absence of said protein product or diminished amounts of said protein product indicating the presence of a mutation in the gene of interest of the human.
The present invention thus provides the art with a useful diagnostic tool in the evaluation of inherited diseases.